Copper alloy



?atented Oct. 16, 1934 ammo STATES;

1,975,803 rice rarer COPPER. i

No Drawing.

Application February 2%. that, Serial No. 713,265

3 Claims. or. rs-n This invention relates to a copper alloy and it has for its object to provide an alloy which will be resistant to corrosion cracking and season cracking, unaflected by mercury or compositions 5 containing mercury, capable of .being'cold drawn and cold worked with a greater reduction of area and muchv higher tensile strength than has heretofore been obtained, while still retaining a good elastic limit thus making the alloy especially l0 suitable for withstanding high pressures so that it serves admirably for cartridge cases and shot gun shells for modern high pressure explosives. Of course, it may also be readily worked hot and is suitable for many purposes when so worked, as it still retains its resistance to corrosion cracking and season cracking, but when worked cold, or if hot worked first and then worked cold, without any annealing or heat treatment, an extreme hardness and strength may be obtained. While an it can be so worked that it is harder and or greater strength than copper, it is very ductile and tough.

With the above object in view, the invention consists in adding to copper a rather small per- -g5 centage of silicon, tin and iron, the percentages rang n as follows:

Percent Silicon 0.1 to 1.00 Tin 0.01 to 0.50 33 Hon 0.01 to 0.75

Balance substantially copper.

kept as low as is commercially possible, or the valuable properties of the alloy will be injurious- 1y afiected- The ingredients may be combined in any of the usual metallurgical ways, for example,

the copper may be melted flrst,'then the iron and silicon added separately or combined as a ferrosilicon compound and finally the tin added to the molten mixture. Instead of this the tin and term-silicon may be added simultaneously to the molten copper, or all the ingredients may be put together cold and the whole then melted.

Two compositions which give the best results The second alloy above set forth is capable of such a small percentage and its action is so modified by the other metals that it has no injurious eifect on the cartridge cases such as has been considered objectionable with copper alloys containing iron.

The alloys above described can be readily worked into seamless tubes and pipes, which is not so easily done with alloys having higher percentages of silicon, iron and tin, yet the final product maintains the other valuable properties of such compositions.

A further important feature of the alloy is that it may be welded by any of the modern welding systems, such as the gas or electric welding methods. Also the alloy may be made into welding rods which are suitable for welding not only the same kind of ,alloy material but other types of copper alloys and the weld metal is particularly satisfactory on account of its high strength and resistance to corrosion of the kinds usually encountered in practice and to season cracking, thereby providing a permanent weld.

Having thus fully described the invention, what It is to be understood that impurities must be I claim a 1. A copper alloy having a composition within substantially the i'cllo range:

Per cent Smmn 0.1 to 1.00 Tin 0.01 to 0.50- Iron 0.01 to 0.75 Balance, substantially copper.

2. A copper alloy having substantially the following composition:

' Per cent Silicon 0.5 Tin 0.25 Iron r 0.25 Balance, copper 99.00

3. A copper alloy be substantially the following composition:

\ Per cent Silicon 1.00 Tin 0.25 v Iron 4 0.25 Balance, co 1. 98.50

B. PRlCE. 

